NASA Bushcraft; thoughts on design
- Thread starter C_Claycomb
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I was all ready to send Sal my sketches and design notes, then started to give serious thought to grind angles and edge thicknesses, and it has dragged out a bit longer than planned. Not helped by work going a little crazy these last three weeks.
I have some worries about the new super steels' ability to hold the sort of edge angles that I consider necessary for cutting performance. My own knives all run somewhere between 20 and 27 degrees total inclusive edge angle. I may just have to accept that the design that suits the steel and majority preferences is not the one that I would choose myself. I have been looking and tweaking the shape looking for a middle ground that will work for everyone.
I have some worries about the new super steels' ability to hold the sort of edge angles that I consider necessary for cutting performance. My own knives all run somewhere between 20 and 27 degrees total inclusive edge angle. I may just have to accept that the design that suits the steel and majority preferences is not the one that I would choose myself. I have been looking and tweaking the shape looking for a middle ground that will work for everyone.
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CTS-BD1 would not be anywhere near a good choice for a outdoor type knife in my opinion. The steel is economy/entry level and would be a disservice to the company, design, and spirit of the intened piece. If we are talking about a "NASA Bushcraft" knife, something better must be used.
^ I only suggested it because it seems to have some carbon like qualities, which people seem to really want on this knife. Everybody was clamoring over the fact you couldn't sharpen S90V on a rock earlier, I thought it might be a good compromise. But no, in any other case, I wouldn't have even brought it up.
if we talking for market purposes in the bushcraft scene,to me at least it seems that a scandi edge would be the better choice,it would be a great oppertunity
that if spyderco chooses to make this knife in the same manner but with a high end carbon steel in CPM3V would take this bushcraft knife to a new level in
every way.
i have 3 skookum bushtools,1 in O1 and 2 in A2 tool steel,toughness and edge holding in A2 is so much better than any knife in O1,also my Koster bushcraft in
CPM3V is again much better than my A2 skookums,at least in toughness and edge retention.
I never had any problems with rust on my carbon steel knives,except for Cru Forge V,which seems to rust very easily,so in CPM3V this spyderco bushcraft knife
with a scandi edge will take any shit with no problems,no bending,chipping or anything else,ergonomics,dimensions and bladeshape are perfect,no changes needed
on that,sharpening CPM3V isn´t that difficult,DMT diafolds in the field,IF sharpening needed in the field at all,DMT bench stones at home should do the job
as needed.
Grtz,Jurgen.
that if spyderco chooses to make this knife in the same manner but with a high end carbon steel in CPM3V would take this bushcraft knife to a new level in
every way.
i have 3 skookum bushtools,1 in O1 and 2 in A2 tool steel,toughness and edge holding in A2 is so much better than any knife in O1,also my Koster bushcraft in
CPM3V is again much better than my A2 skookums,at least in toughness and edge retention.
I never had any problems with rust on my carbon steel knives,except for Cru Forge V,which seems to rust very easily,so in CPM3V this spyderco bushcraft knife
with a scandi edge will take any shit with no problems,no bending,chipping or anything else,ergonomics,dimensions and bladeshape are perfect,no changes needed
on that,sharpening CPM3V isn´t that difficult,DMT diafolds in the field,IF sharpening needed in the field at all,DMT bench stones at home should do the job
as needed.
Grtz,Jurgen.
The Mastiff
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Is it only the corrosion resistance , or lack of it, or is something else.
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3V sounds like it has good properties, and better corrosion resistance than O-1, but I would not chose it for one of my canoe expeditions, or for one of my friends to take to the jungle, if there was a stainless alternative. I guess one could look at applying some sort of DLC treatment, or similar, but that isn't the avenue that we have been going down.
I have passed Sal what you might call my first issue of the design; better than a draft, but still open to changes based on his feedback. I have also asked for his opinions (based on testing) on some of the steels that folk have been discussing.
Best wishes and happy Thanksgiving.
I have passed Sal what you might call my first issue of the design; better than a draft, but still open to changes based on his feedback. I have also asked for his opinions (based on testing) on some of the steels that folk have been discussing.
Best wishes and happy Thanksgiving.
carbon steel knives with scandi edges are used for century´s in the scandinavian part of the world,or wherever in the northern world, a lot of wet and cold
circumstances are going on there,so for me it´s not an issue to use carbon steel,also to my feeling no stainless steel can compete with a well HT carbon
steel blade,especially with a scandi edge,as well for edge holding also for cutting capabilities,maintainance is very easy,put it dry in the sheath,even a wet
stainless steel knife will rust in his sheath if not maintained.
I for myself never see any advantage for a FFG compared to a scandi edge for a bushcraft knife,I really want to have the best cutting performance for
any task,which for me only a scandi edge can do,a magnificent designed knife like the spyderco bushcraft with his awesome ergonomics AND a super
steel in CPM3V will outperform any stainless steel knife in my humble opinion,especially taken with a scandi edge,which is what a bushcraft knife is
meant to have,a scandi edge.
circumstances are going on there,so for me it´s not an issue to use carbon steel,also to my feeling no stainless steel can compete with a well HT carbon
steel blade,especially with a scandi edge,as well for edge holding also for cutting capabilities,maintainance is very easy,put it dry in the sheath,even a wet
stainless steel knife will rust in his sheath if not maintained.
I for myself never see any advantage for a FFG compared to a scandi edge for a bushcraft knife,I really want to have the best cutting performance for
any task,which for me only a scandi edge can do,a magnificent designed knife like the spyderco bushcraft with his awesome ergonomics AND a super
steel in CPM3V will outperform any stainless steel knife in my humble opinion,especially taken with a scandi edge,which is what a bushcraft knife is
meant to have,a scandi edge.
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I strongly advised against the use of D2 for the original knife due to sharpening problems. The first prototypes were not dead flat and D2 took 45 minutes and a good deal of 120 grit paper to flatten up. Sure, you can do it with diamond, but the majority of the people I know who practice bushcraft are not steel junkies and do not necessarily have all the Gucci kit to easily maintain the high abrasion resistant steels. Especially not when you have so much surface to keep flat.
With O-1 available on the original, I am less worried about the next knife having a harder to sharpen blade, but there are a lot of people who like flat grinds, myself included, so a 3V scandi hasn't really had a look-in this time. It is an interesting idea for a sprint run...if Sal is listening
I don't know more than one or two people who would like one, but there seem to be plenty of people on the forums that like the idea.
Also, this new knife is meant to be something other than a bushcraft knife. More utility, maybe more general. I want it to still be good at whittling and cutting wood, but unlike the original, this is not the total overriding design driver that it was before.
Someone suggested that I was a little out of my comfort zone on this one. I am not sure exactly what they meant, but it was certainly easier to design the first knife with the clear purpose that the knife was for traditional, Boreal forest inspired, bushcraft; heavy on wood carving and crafting, not just fire wood splitting and food prep.
With O-1 available on the original, I am less worried about the next knife having a harder to sharpen blade, but there are a lot of people who like flat grinds, myself included, so a 3V scandi hasn't really had a look-in this time. It is an interesting idea for a sprint run...if Sal is listening
I don't know more than one or two people who would like one, but there seem to be plenty of people on the forums that like the idea.Also, this new knife is meant to be something other than a bushcraft knife. More utility, maybe more general. I want it to still be good at whittling and cutting wood, but unlike the original, this is not the total overriding design driver that it was before.
Someone suggested that I was a little out of my comfort zone on this one. I am not sure exactly what they meant, but it was certainly easier to design the first knife with the clear purpose that the knife was for traditional, Boreal forest inspired, bushcraft; heavy on wood carving and crafting, not just fire wood splitting and food prep.
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The Mastiff
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Hi Chris. It was me. It certainly wasn't meant as an insult. I meant you were considering other materials than you typically use for this design.
IMO, most of the steels discussed here will need a good sharpening stone of some kind. The high carbide stainless especially. Some of these steels will laugh off attempts at removing steel with non synthetic stones of the usual kind such as "arkansas" stones. Several of these are noticeably more stubborn than D2, but these steels do well with the blade forum crowd. I'm not sure about your target market though.
We do go on about the different steels and how they perform however Sal has the real info on performance from his lab tests on these steels which he doesn't publish. You are in good hands there, in my opinion.
Joe
Lack of corrosion resistance, wet conditions where wiping down a blade means NOTHING because everything is soaked to the core. Sometimes you just CAN'T oil and dry a knife. Beyond that, modern stainless like S35VN blow most carbon steels out of the water in pretty much every category.
They were used for centuries because they had nothing else. Do you REALLY think, that given the choice between two knives, one made of 1095 and the other made of CTS-XHP, an ancient explorer would go with the one that needs constant maintenance and will decay over time more readily? I somehow don't think so. It's the same as how when we discovered copper tools we gave up using flint.
I'm afraid then that you're feeling isn't scientifically correct here. In pretty much all aspects, modern stainless are equal or SUPERIOR to even the best treated carbon steel. The only way to get around that is something like CPM-M4, and even then, the stuff basically ROTS if not treated like a living thing.
And you CAN'T always "put it away dry" What if it's raining, or snowing, or just plain WET? I've been in situations where I couldn't dry my knives because there was NOTHING TO DRY THEM WITH. I didn't need to worry, because S30V don't mind being soaked.
And as for them rusting in the sheath: Not really as much as you'd think, no. I've put away PLENTY of soaked stainless, often dirty, bloody, or covered in fish guts. It can stay like that for a good week or two before I need to clean it up. I'd take S35VN over almost any other steel I could be offered. The stuff is tough like A2, stainless like S30V, sharpens like 14c28n Sandvik, and holds an edge like 440V.
Trying to get me to use carbon steel is like trying to get me to drive a model T ford instead of a Tesla. No thanks, I'll take the space-age car.
Sal Glesser
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Hi Chris,
Got your drawings, thanx. We'll be studying them.
sal
Got your drawings, thanx. We'll be studying them.
sal
well,checked it out,S30V or S35VN aren´t all that corrosion resistant,about 14% chromium makes them a low end stainless steel,also S35VN isn´t as tough for edge holding compared to S30V,
if a high end stainless steel is needed,Bohler M390 would be a better choice maybe,very high wear and corrosion resistance,20% chromium,I have a Survive knife 4.1 in this steel,can get it awfully sharp
and stays it for a long time,can take some abuse too !
if a high end stainless steel is needed,Bohler M390 would be a better choice maybe,very high wear and corrosion resistance,20% chromium,I have a Survive knife 4.1 in this steel,can get it awfully sharp
and stays it for a long time,can take some abuse too !
^ It's not just the chromium that makes them resistant to corrosion. It has nitrogen in it, which improves that category, and it also has molybdenum.
And it is in NO way, a low end stainless steel. Where are you getting this data from? It's more or less equal to M390 according to everything I've seen, as well as my own experience. I'd say EITHER of the steels would be fantastic, I'm just curious why you think S35VN isn't that good a steel.
According to crucible's data sheet: CPM S35VN is a martensitic stainless steel designed to offer improved toughness over CPM S30V. It is also easier to machine and polish than CPM S30V. Its chemistry has been rebalanced so that it forms some niobium carbides along with vanadium and chromium carbides. Substituting niobium carbides for some of the vanadium carbides makes CPM S35VN about 15-20% tougher than CPM S30V without any loss of wear resistance. CPM S35VN’s improved toughness gives it better resistance to edge chipping. Because both vanadium and niobium carbides are harder and more effective than chromium carbides in providing wear resistance, the CPM stainless blade steels offer improved edge retention over conventional high chromium steels such as 440C and D2.
I've tested every claim on that sheet. I took a spartan and tested everything said in the above regarding performance. Passed with flying colors.
And it is in NO way, a low end stainless steel. Where are you getting this data from? It's more or less equal to M390 according to everything I've seen, as well as my own experience. I'd say EITHER of the steels would be fantastic, I'm just curious why you think S35VN isn't that good a steel.
According to crucible's data sheet: CPM S35VN is a martensitic stainless steel designed to offer improved toughness over CPM S30V. It is also easier to machine and polish than CPM S30V. Its chemistry has been rebalanced so that it forms some niobium carbides along with vanadium and chromium carbides. Substituting niobium carbides for some of the vanadium carbides makes CPM S35VN about 15-20% tougher than CPM S30V without any loss of wear resistance. CPM S35VN’s improved toughness gives it better resistance to edge chipping. Because both vanadium and niobium carbides are harder and more effective than chromium carbides in providing wear resistance, the CPM stainless blade steels offer improved edge retention over conventional high chromium steels such as 440C and D2.
I've tested every claim on that sheet. I took a spartan and tested everything said in the above regarding performance. Passed with flying colors.
Got it from a independent source called z-knives, an American source which even developed an smartphone app which has a real big datasheet, also had a few knifes with S30V, bad edgeholding despite what a lot of sources said about it, even experimented with different edge geometry to get better performance, no better results with that also, one of these knives was a Spartan actually, all my carbon tool steel knives performs way better than S30V, what comes close to it is Bohler N690, which I experimented a lot with, and Bohler M390, but this steel is in the experimental Phase a bit more on this moment.
^ If you had knives with S30V that had bad edge holding, you MAY have had burned edges or a soft heat treat. I've used S30V a LOT, that stuff isn't bad at edge holding, and I've had it out-cut ESEE knives on multiple occasions. From all the data and testing I have seen and done, carbon tool steel is vastly inferior to modern stainless steel. I've actually shaved bits of 1095 off the blade with a piece of S35VN.
Funny you would actually find N690 a better steel, actually. It's actually a modified version of 440C, which I get the feeling you wouldn't like one bit. Granted, it's good steel, but I prefer S30V and it's family to N690.
Funny you would actually find N690 a better steel, actually. It's actually a modified version of 440C, which I get the feeling you wouldn't like one bit. Granted, it's good steel, but I prefer S30V and it's family to N690.